Field of the Invention
The present invention relates to a printing apparatus for performing a printing operation using an ink ejection head for ejecting ink and a reaction liquid ejection head for ejecting reaction liquid reacting with the ink.
Description of the Related Art
An ejection head in an inkjet printing apparatus causes, in addition to ink droplets for printing an image, mist-like minute ink droplets called mist that do not contribute to the formation of an image. The minute ink droplets float in air and are attached to the ejection head and various parts in the printing apparatus to thereby cause an ejection defect of the ejection head, a deteriorated function of the printing apparatus, or a deteriorated image quality. Another printing apparatus has an ejection head to eject not only ink for printing an image but also reaction liquid reacting with ink. In the case of this type of printing apparatus, mist of reaction liquid may be generated when the reaction liquid is ejected and may be attached to the ejection port face of the ejection head for example. The reaction liquid attached to the ink near the ejection port of the ejection head promotes the fixed adhesion of the ink, which causes the inconvenience due to the mist to be more remarkable.
The specification of US Patent Laid-Open No. 2006/0238561 discloses a configuration of a printing apparatus including a plurality of ejection heads in which the respective ejection heads have therebetween a suction duct for sucking the mist and a blowoff duct for blowing air that are provided to be adjacent to each other.
In the case of the printing apparatus disclosed in the specification of US Patent Laid-Open No. 2006/0238561, a plurality of ejection heads, the suction duct, and the blowoff duct are provided along a cylinder face in a radial manner. Thus, different positions have different inclination directions to the vertical direction. Thus, a certain position causes liquefied mist attached to the duct interior to fall in drops due to the gravitational force and the liquid may fall in drops from the suction hole of the duct onto a medium.